Manual - Chapter 1 Engine

16. Examination and renovation: bearings and oil seals

  1. Ball bearings should be washed thoroughly to remove all traces of oil then tested as follows. Hold the outer race firmly and attempt to move the inner race up and down, then from side to side. Examine the bearing balls, cages and tracks, looking for signs of pitting or other damage. Finally spin the bearings hard; any roughness caused by wear or damage will be felt and heard immediately. If any free play, roughness or other damage is found the bearing must be removed.
  2. Roller bearings are checked in much the same way, except that free play can be checked only in the up and down direction with the components concerned temporarily reassembled. Remember that if a roller bearing fails it may well mean having to replace, as well as the bearing itself. one or two components which form its inner and outer races. If in doubt about a roller bearing's condition, renew it.
  3. Do not waste time checking oil seals; discard all seals and O-rings disturbed during dismantling work and fit new ones on reassembly. Considering their habit of leaking once disturbed, and the amount of time and trouble necessary to replace them, they are relatively cheap if renewed as a matter of course whenever they are disturbed.

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